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The Bureau of Environmental Health and Safety (BEHS), Idaho Division of Health,
Department of Health and Welfare, prepared this Health Consultation under its
cooperative agreement with the Agency for Toxic Substances and Disease Registry
(ATSDR) to document the BEHS response to several Oldtown Community Advisory
Group e-mails requesting more in-depth explanations about our activities and
decisions. The health consultation addresses those specific issues raised in
the e-mails. In the discussion section you will see a bold heading with accompanying
explanatory text. The bolded, italicized heading delineates the issue/question
posed to BEHS. The text that follows is our explanation to the issue/question
raised.

SITE DESCRIPTION AND BACKGROUND

Poles Inc. is located in Oldtown just south of Pend Oreille River in the Panhandle
of Northern Idaho. The facility has produced pentachlorophenol-treated utility
poles since 1945. The facility currently operates nine months out of the year.
An elementary school (Idaho Hill Elementary) and multiple residences are within
proximity of the site.

In fall 2000, teachers from Idaho Hill Elementary and community members formed
the Healthy Building Committee. The committee requested the Idaho Department
of Environmental Quality (IDEQ) to investigate an irritating chemical smell
coming from the facility during its pole treating process. Following the request,
IDEQ performed an evaluation of potential inhalationexposure to PCP
using two air dispersion models called the Back Model and the SCREEN3 Model
(IDEQ 2001). BEHS reviewed IDEQ's report and determined that modeled PCP concentrations
may pose a public health concern if they are representative of actual exposure
levels. Therefore, because of multiple uncertainties regarding the use of computer
models, BEHS recommended that a thorough environmental investigation be conducted
at the Oldtown site. Details are summarized in the previous Health Consultation
titled "Evaluation of Potential Pentachlorophenol Air Contamination Based
on the Idaho Department of Environmental Quality April 2001 Air Modeling Results"
(BEHS 2001a). BEHS formed the Community Advisory Group (CAG) during the process
of drafting the previous Health Consultation to ensure community involvement.
In summary, BEHS suggested that the environmental investigation should include
multiple environmental
media and that it should be expanded to focus on potential contaminants
other than PCP. In August 2001, the Environmental Protection Agency (EPA) Superfund
Technical Assessment and Response Team (START) completed an Integrated Assessment
(IA) Sampling and Quality Assurance Plan (SQAP) for Poles Inc., and subsequent
environmental sampling. BEHS reviewed the SQAP and provided review comments
in the health consultation titled, "Evaluation of EPA's Integrated Assessment
Sampling and Quality Assurance Plan for Poles, Inc." Prior to the start
up of the sampling activities, START reviewed the suggestions and agreed to
incorporate them in its IA SQAP.

This health consultation addresses questions raised by the Oldtown CAG before
the EPA IA final report was released in January 2002. By the time this health
consultation is published, BEHS will have reviewed the IA sampling results and
begun preparation of a public health assessment for the site.

DISCUSSION

Focus of the Bureau of Environmental Health and Safety (BEHS) and the Agency for Toxic Substances and Disease Registry (ATSDR) as Public Health Agencies:

BEHS and ATSDR assess chemical exposures or the potential for exposures and
assess whether or not people may experience harmful health effects from those
exposures. Unlike the EPA health risk assessment process that addresses current
or future exposures from a regulatory perspective, the public health assessment
process looks at past, present and future exposures from a human health effects
perspective. BEHS and ATSDR determine the chemical(s) of concern based on environmental
data collection conducted by others, assess the hazards associated with those
chemicals and determine if there was, is or will be exposure. The level of hazard
to people based on the magnitude and duration of the exposure is then assessed.
In the case of Oldtown, BEHS is still awaiting the sampling data results from
EPA to conduct the public health assessment. Until environmental sampling data
is received, BEHS cannot definitively state that people are being exposed to
pentachlorophenol at levels that would result in adverse health effects.

Cancer Investigation and Health Outcome Data Review:

BEHS has never received the names of teachers at Idaho Hill Elementary School
who are said to have cancer. To date, only anecdotal information about the numbers
of people with cancer in the school and community has been received. BEHS has
approached the school districts to try and obtain information about the teachers
to compare to the Cancer Data Registry of Idaho's (CDRI) database. The school
districts were reluctant to provide the key pieces of information (birthdates
and social security numbers if available) necessary for the CDRI to conduct
a meaningful cancer analysis for the school. The school districts were willing
to provide CDRI with the names and dates of employment. However, the CDRI did
not feel that the name identifiers alone could be effectively validated against
their database because the chance of errors in matching individuals on name
alone was too high. Because of privacy and confidentiality issues, BEHS and
CDRI are not in a position to take the list of names and contact people individually
to see whether or not they have been diagnosed with cancer in Idaho.

BEHS is currently conducting another cancer incidence analysis for the combination
of three zip codes (Oldtown, Newport, and Priest River). The analysis results
will be compared to the rates in both the remainder of the state of Idaho and
the remainder of the county (rural area). BEHS will then evaluate over 24 cancer
types, as well as all cancer types combined by gender. CDRI has a 99.6% case
completeness rate and a 98.6% accuracy rate. In other words, BEHS has great
confidence that those people in your communities that were diagnosed with cancer
in Idaho or neighboring states are included in their database.

Lastly, BEHS is waiting for environmental data to provide evidence that an
epidemiological study or biological testing (for example, urine, blood, or fat
testing) is warranted. Unfortunately, there is no other comprehensive, non-cancer
disease registry in the State of Idaho. BEHS will utilize the data that is currently
available. Current efforts at the Federal level to begin tracking chronic diseases
other than cancer may give local, state, and federal public health agencies
more extensive health outcome data to use in the future.

Biological Testing:

Specific questions have been asked about the costs, invasiveness, and logistics
of having body fat tested for the, presence of dioxin (impurity found in pentachlorophenol).
BEHS does not recommend body fat testing for dioxin until environmental data
support the need for such testing. However, BEHS has done some research and
found that there are very few laboratories that have the ability to analyze
body fat for dioxin. The laboratory analytical techniques are complicated, therefore
the tests are expensive. The cost is dependent upon the number of samples submitted
to the laboratory and the detection limit that is requested. An individual analysis
is approximately $1,500. The amount of body fat that is required for analysis
varies by analytical technique, but the approximate amount is 10 or more grams
of body fat. The fat extraction process is dependent upon the physician, as
well as the physician costs. ATSDR's toxicological profile for pentachlorophenol
cites references that evaluated body fat testing for dioxin.

Use of the Term Health Effects:

BEHS and ATSDR use the term "health effects" to denote that there
may be a change in the health status of an individual or an effect on health.
The agencies judge that the terminology "health effect" is appropriately
used in the BEHS health consultation and is consistent with how other public
health agencies present information. BEHS does not feel that it implies a "healthy
effect" from exposure to pentachlorophenol and did not assume that others
would think that it implied a positive change in one's health status.

Use of the Term "Exposure" in Conjunction with "Potential:"

Until BEHS has received environmental sampling data identifying that contaminants
are leaving the site resulting in off-site exposures, BEHS does not feel it
is appropriate to eliminate the word "potential." BEHS, as a public
health agency, can not definitively state there is exposure to pentachlorophenol
or determine resulting impacts on human health without supporting environmental
data.

Has Pentachlorophenol in the Air in Oldtown Reached Hazardous Levels? How do you determine what a hazardous level is?

As partners with ATSDR, BEHS uses Minimal Risk Levels (MRL's) to calculate
non-cancer risk and adopts a cancer slope factor from EPA to calculate cancer
risk. At or below that MRL and at or below calculated cancer unit risk, we consider
the exposure to be without apparent risk of health effects.

The ATSDR toxicological profile for pentachlorophenol documents that the following
MRL has been established: 0.005 mg/kg/day for acute-duration oral exposure and
0.001 mg/kg/day for both intermediate-duration and chronic-duration oral exposure.
Currently there are no inhalation MRLs available for pentachlorophenol. However,
oral data is used to assess inhalation exposure when inhalation data are not
available, as in the case of pentachlorophenol.

EPA has developed an oral slope factor for pentachlorophenol, 0.12 (mg/kg/day)-1,
based on a feeding study in mice conducted as part of the National Toxicology
Project. Since there is no inhalation slope factor available for pentachlorophenol,
BEHS adopted the EPA oral slope factor value as an inhalation slope factor to
assess risk. BEHS is aware that there are uncertainties associated with using
an oral factor for inhalation purposes. The State of California published an
inhalation slope factor for pentachlorophenol, 0.018 (mg/kg/day)-1.
It is not known if the California value more accurately represents the carcinogenic
toxicity of pentachlorophenol than the EPA value. BEHS will use EPA's value
to be more protective and to determine a site-specific risk-based ambient air
concentration. In order to do so, the potential for exposure to pentachlorophenol
via other exposure routes, such as dust inhalation, incidental soil ingestion,
or dermal uptake, should also be evaluated. If there are other complete exposure
pathways, then the acceptable concentration of pentachlorophenol vapor in air
would have to be lower because other pathways also contribute to cumulative
cancer risk. So far, BEHS does not have data from other environmental media
needed to make a final decision.

Finally, BEHS is using the standard risk assessment/public health assessment
procedures currently recommended by EPA and ATSDR, respectively. Pentachlorophenol
is presently under EPA's review for a new oral cancer slope factor. As soon
as that is finalized, BEHS will adapt the new EPA factor. ATSDR's MRLs were
revised and published in September 2001. BEHS is confident it is utilizing the
most up-to-date peer-reviewed science for conducting the public health assessment.

BEHS's Use of the Term "Weak" in Relation to Pentachlorophenol as a Carcinogen:

BEHS stated in its first health consultation for Oldtown that "there is
weak evidence pentachlorophenol causes cancer in humans." On page five
of the ATSDR Toxicological Profile for pentachlorophenol (both the draft document
and the final September 2001 document) under the section titled, "How can
pentachlorophenol affect my health," the following paragraph can be found:

"An increased risk of cancer has been shown in some laboratory animals
given large amounts of pentachlorophenol orally for a long time. There is
weak evidence that pentachlorophenol causes cancer in humans. The International
Agency for Research on Cancer (IARC) has determined that pentachlorophenol
is possibly carcinogenic to humans, and the EPA has classified pentachlorophenol
as a probable human carcinogen."

The toxicological profile is a peer-reviewed profile that, as stated in the
foreword, "identifies and reviews the key literature that describes a hazardous
substance's toxicological properties." It also states that "this profile
reflects ATSDR's assessment of all relevant toxicologic testing and information
that has been peer-reviewed. Staff of the Centers for Disease Control and Prevention
and other federal scientists have also reviewed the profile. In addition, this
profile has been peer-reviewed by a nongovernmental panel and was made available
for public review.' ATSDR, even after reviewing copious amounts of peer-reviewed
literature, continues to use the same language. Additionally, after reviewing
many animal studies and epidemiology studies, EPA classified pentachlorophenol
as a "probable human carcinogen." The IARC classified it as "possibly
carcinogenic to humans". Pentachlorophenol is not currently classified
as a known "human carcinogen" because there are not enough human epidemiologic
studies supporting the classification.

BEHS noted in one of the community meetings that IDEQ did not consider pentachlorophenol
as a carcinogen when establishing Idaho's ambient air standard. That decision
was a professional judgment made at that time. IDEQ is now considering revising
Idaho's standard to err on the side of protection. However, decisions made by
the State of Idaho do not influence the scientific data EPA or ATSDR utilizes.

The Banning of Pentachlorophenol:

BEHS is not in a position to ban the use and manufacture of pentachlorophenol.
BEHS, like ATSDR, can only make recommendations. In Oldtown, BEHS has not seen
evidence, to date, to support a position that pentachlorophenol use at Poles,
Inc. is presenting a situation immediately dangerous to life and health. If
that situation were found, BEHS could work with IDEQ and the Idaho Department
of Agriculture to control the facility's use of the chemical. BEHS cannot ban
the use and manufacture of a chemical.

EPA reevaluates all pesticides that were registered before November 1984. When
EPA completes the review and risk management decision for a pesticide that is
subject to reregistration, the Agency generally issues a Reregistration Eligibility
Decision (RED) document. The RED summarizes the risk assessment conclusions
and outlines any risk reduction measures necessary for the pesticide to continue
to be registered in the U.S. If pentachlorophenol is not eligible to be reregistered
during its RED, IDEQ and BEHS will respond to that final decision accordingly.

CONCLUSION AND RECOMMENDATION

BEHS anticipates that the public health assessment for the site will provide
a comprehensive picture of the issues in Oldtown. No recommendations are indicated
at this time. The public health assessment, due spring 2002, will evaluate the
issues in Oldtown and provide public health recommendations.

PUBLIC HEALTH ACTION PLAN

BEHS, IDEQ, ATSDR, and EPA have conducted or are currently planning the following
public health actions:

BEHS formed the Oldtown CAG, sponsored multiple public meetings, and provided
a public availability session. BEHS is currently the point of contact for
the CAG and will routinely provide CAG with updates about Oldtown site activities
from all involved agencies.

IDEQ conducted a preliminary soil sampling at the facility and on the school
playground to determine the possibility of soil contamination. BEHS will review
the IDEQ sampling results as part of the development of a public health assessment
for the site.

Community members requested EPA conduct a preliminary assessment for the
site. EPA conducted an IA of the site and has involved IDEQ, BEHS, ATSDR,
and the site owner (Poles Inc.). The IA was competed in August and a final
report was published in January 2002. BEHS is currently evaluating the environmental
sampling results as part of the development of a public health assessment
for the site.

BEHS is currently drafting a public health assessment for the site. A draft
will be available for technical comment by spring 2002. The public health
assessment will make recommendations about the need for further actions at
the site and within the community.

BEHS is working cooperatively with the State of Idaho Cancer Analysis Working
Group to evaluate cancer rates for the community and among Idaho Hill Elementary
school teachers. The Cancer Analysis Working Group is comprised of the State
of Idaho Epidemiologist, representatives of BEHS, representative of the Bureau
of Vital Records and Health Statistics, and the Cancer Data Registry of Idaho.

The Idaho Bureau of Environmental Health and Safety prepared this Health Consultation
under a cooperative agreement with the Agency for Toxic Substances and Disease
Registry (ATSDR). It is in accordance with approved methodology and procedures
existing at the time the health consultation was initiated.

Gregory V. Ulirsch
Technical Project Officer, SPS, SSAB, DHAC

The Superfund Site Assessment Branch (SSAB), Division of Health Assessment
and Consultation (DHAC), ATSDR has reviewed this health consultation and concurs
with its findings.